Earth boring device and method of use

ABSTRACT

A borehole tool for drilling in a formation is disclosed. The tool is of the type that incorporates a sphere for deploying cutting elements for hydraulically expanding the same for borehole reaming or enlargement during drilling. The tool conveniently includes a reset function where the cutting elements can be reset to a retracted position within the cutter housing. Advantageously the reset of the cutter elements is achievable by simply removing a cutting bit at the end of drill string and inserting the reset member in the form of a elongate rod through the end of the drill string to urge the sphere or ball back to the top of the drill string for retrieval and resetting the movable member which allows for fluid flow redirection within the cutter housing. The reset function can be achieved on site thus avoiding significant expenses and downtime typically associated with systems that cannot be reset onsite.

FIELD OF THE INVENTION

The present invention relates to an earth boring device and more particularly, the present invention relates to a method and apparatus for stabilizing a drill string during earth boring and expansion reaming.

BACKGROUND OF THE INVENTION

Drilling tools of all varieties are known in the art. One of the problems that has been pervasive in the solutions presented by the prior art relates to dependability of the tool and also expediency when resetting the reamer function once it has been deployed. As has been identified in the prior art, resetting the ball used to redirect the drilling fluid can be arduous and requires removal of the tool from within the formation partial disassembly and subsequent reassembly. All of these operations are time intensive and are therefore very costly in a drilling operation. The present invention seeks to mitigate the limitations with existing arrangements to provide a more effective drilling tool which may be easily and quickly reset in the field in order to keep things moving for maximum efficiency in a notoriously expensive operation.

Typical arrangements used in drilling for oil and gas may include a stabilizer and enlargement reamer. The stabilizer is used to prevent torsions and other forces from damaging or changing the direction of the string in use. The reamers are useful to enlarge the bore hole and are retractable within the body of the tool. Examples of such tools have been delineated in the prior art, an example of which is shown in United States Patent Publication No. U.S. 2012/0279784, the author which is Harvey et al.. The technology relates to a slide reamer and stabilizer tool. The tool has reamer cartridges which can be removed and replaced with stabilizer cartridges having stabilizer inserts and hard faced stabilizer cones.

Turning to the expandable reamers, U.S. Pat. No. 7,493,971 issued Feb. 24, 2009 to Nevlud et al., teaches a concentric expandable reamer. This is one of the earlier reaming arrangements which provides for movable arms which are deflectable radially outward from the reamer for borehole enlargement. A fairly complex mechanism is disclosed in the patent and there is no discussions regarding resetting or repositioning of the movable arms in an expeditious manner.

Radford et al., in U.S. Pat. No. 7,900,717, issued Mar. 8, 2011, further advances the expandable reamer technology. In this arrangement a push sleeve is disposed in the inner bore of the body and is coupled to each one of the blades to effect axial movement along a track to an extended position responsive to exposure to a pressure or force of drilling fluid in the flow path of the inner bore. Similar to the Nevlud et al. document, this document does not set forth any instructions regarding the reset of the blades.

Radford et al., further expands on the stabilizer with reamer elements in U.S. Pat. No. 8,020,767, issued Oct. 4, 2011. In this arrangement the blades may include at least one roller element for reaming a wellbore.

Further still, Radford et al. further delineates reamers in U.S. Pat. No. 7,681,667, issued Mar. 23, 2010.

Despite the panacea of developments in this area of technology, there is a notable absence of expandable reamer with a reset function that can be expeditiously effected in the field. The present invention addresses the absence of the reset feature to present a more efficient arrangement.

SUMMARY OF THE INVENTION

One object of the present invention is to provide an improved reaming tool.

A further object of one embodiment of the present invention is to provide an expandable reamer apparatus for subterranean drilling, comprising: a tubular body having a longitudinal axis and a trailing end for connecting to a drill string; fluid pressure actuable cutting members movable from a storage position retracted within said tubular body to a use position extending outwardly of said tubular body for reaming and/or expanding the diameter of a borehole; a drilling fluid flow redirection member movably mounted within said tubular body from a first inactive position to a second active position where fluid is redirected adjacent said fluid pressure actuable cutting members to actuate said cutting members to said use position.

Yet another object of one embodiment of the present invention is to provide an expandable reamer apparatus for subterranean drilling, comprising: a tubular body having a longitudinal axis and a trailing end for connecting to a drill string; a drilling fluid flow path extending through said tubular body; fluid actuated cutting members movable from a storage position retracted within said tubular body to a use position extending outwardly of said tubular body for reaming and/or expanding the diameter of a borehole; a drilling fluid flow redirection member movably mounted within said tubular body from a first position proximate said cutting members to a second position distal from said cutting members to facilitate drilling fluid flow redirection whereby fluid pressure is sensed by said cutting members for movement to said use position; and an actuator for actuating movement of said fluid flow redirection member.

A further object of one embodiment of the present invention is to provide a method for reaming a borehole in a subterranean formation, comprising: positioning an expandable reaming apparatus within a subterranean formation, said reaming apparatus having having a tubular body, a drilling fluid flow path extending through said tubular body, fluid actuated cutting members movable from a storage position retracted within said tubular body to a use position extending outwardly of said tubular body for reaming and/or expanding the diameter of a borehole; introducing drilling fluid into said reaming apparatus; redirecting said drilling fluid flow in said reaming apparatus with a redirection member movably mounted within said tubular body from a first position proximate said cutting members to a second position distal from said cutting members to facilitate drilling fluid flow redirection whereby drilling fluid pressure is sensed by said cutting members for movement to said use position; and reaming a borehole in said subterranean formation by rotation and displacement of the reamer apparatus within said subterranean formation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is plan view of one embodiment of the present invention;

FIG. 1A is an isolated view of the cutter housing of the present invention;

FIG. 1B is a cross section of FIG. 1A;

FIG. 2 is a longitudinal view of FIG. 1;

FIG. 2A is an enlarged view of the cutter housing of the tool illustrating the actuating member in a first position;

FIG. 2B is an enlarged view similar to FIG. 2A with the collet sleeve in the active position;

FIG. 3 is an enlarged sectional view illustrating the disposition of the reset member in a first position within the tool;

FIG. 4 is a longitudinal sectional view illustrating the reset member in a final position within the tool;

FIG. 5 is a longitudinal cross section view of an alternate embodiment of the present invention;

FIG. 5A is an enlarged sectional view of the tool shown in FIG. 5 illustrating the disposition of the collet sleeve;

FIG. 5B is a longitudinal cross sectional view of the tool illustrating the position of the actuating member within the tool in a first position;

FIG. 5C is a view similar to FIG. 5B illustrating the position of the actuating member in a second position;

FIG. 6 is a view in longitudinal cross section illustrating the position of the reset member within the tool in a first position; and

FIG. 7 is a view similar to FIG. 6 with the resetting operation complete. Similar numerals used in the Figures denote similar elements.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings and particularly FIG. 1, numeral 10 generally denotes one embodiment of the earth boring tool. The tool includes, as is typical with these arrangements, a first stabilizing member 12 referred to in the art as a sub which is threadibly connected to the cutter housing 14. Extending coaxially and in threaded connection from the cutter housing 14 is a piston housing 16. One end of the piston housing 16 has a bottom sub 18 which has a threaded segment 20 for typically receiving a drill bit head (DBH).

FIGS. 1A and 1B illustrate greater detail concerning the cutter housing 14. As is evident from FIG. 1A, the cutter housing 14 provides plurality of helical flutes 18. The helices are disposed at an angle of 27.6 degrees as a first possibility. It will be appreciated by those skilled in the art that this is an example of the invention. Between the flutes 18 are a plurality of raised segments 20 each having a plurality of apertures 22 extending there along in equidistant relation. Referring to FIG. 1B, each of the apertures 22 retains a piston 24 to which is connected a cutting element 26 shown best in FIG. 1. Each cutting element, 23 in this example, includes a plurality of cutting buttons 24 which may be made of a sufficiently durable material such as tungsten carbide that is widely used for this purpose. As is evident from FIG. 1B a longitudinal shaft 26 extends through the entire cutter housing 14 as well as all the elements connected thereto set forth regarding the discussion of FIG. 1.

Turning now to FIGS. 2, through 2B, shown in FIG. 2 a longitudinal cross-section of the tool 10 with the structural relationship of the individual members as discussed in FIG. 1. The tool 10 in FIG. 2 is depicted in a state where the cutting elements 26 are in a retracted state within cutter housing 14. In this embodiment, there is an elongate member 28 disposed coaxially with cutter housing 14. The elongate member 28 is hollow and allows for fluid flow therethrough so that fluid can flow from sub 12 to sub 18 as is known in the art. The typical fluid is drilling mud well known to those skilled. The elongate member 28 is mounted for slidable movement within cutter housing 14 and extends substantially the full length of the housing 14. A terminal end 30 of member 28 provides a plurality of slots 32 the purpose of which will be discussed hereinafter. Slots 32 define a series of individual fingers 34. Elongate member 28 is more commonly referred to as a collet sleeve in the art and will be referred to as such herein after. The collet sleeve 28 at an opposed end from fingers 34 referenced by numeral 36 includes a substantially frustoconical end portion 38, the purpose of which will be discussed hereinafter. Collet sleeve 28 is movable coaxially within the tool 10 as mentioned herein previously by making use of an actuating member 40 shown in FIG. 3. The actuating member 40 comprises a sphere which is positionable within the tool in a position as noted in FIG. 3.

Disposed within piston housing 16 is a parking tube 42 which receives collet sleeve 28. This will be discussed in greater detail in forthcoming paragraphs. The arrangement is disposed such that fluid communication is maintained.

The actuating member or sphere 40 is shown in a loaded position in FIG. 2A. It is simply dropped into position by a user through the opening of cutter housing 12. Sphere 40 is retained within the end of collet sleeve 28 by a stop member 44 comprising a ring of reduced diameter relative to the inside diameter of the collet sleeve 28. At an opposed end 46 of collet sleeve 28, the finger 34 also include a stop member 48 associated with each finger 34 in the form of a radially extending boss. A bushing 50 includes a channel 52 to receive the individual stop members 48. A plurality of O ring type seals 54 are distributed about the periphery of collet sleeve 28 to ensure fluid flow does not contact piston 24 which would otherwise result in activation and subsequent projection of the cutting elements 28.

FIG. 2B illustrates the position of the collet sleeve 28 within parking tube 42. The movement occurs as a result of the mass of the sphere 40. At end 56 of parking tube 42, there is an internal channel 58 terminating in a stop member 60. Channel 58 allows for reception of stops 48 of fingers 34 with the stop 60 engaging the terminal portion of each finger 34 to prevent further axial movement within parking tube 42. In order to add stability in this position a locating member or centralizing bushing 62 is positioned to surround parking tube 42. Centralizing bushing 62 has a plurality of equidistant and radially disposed apertures 64 that provide fluid communication with the exterior of parking tube 42 and the interior volume defined by the space between parking tube 42 and the inside wall 66, denoted by numeral 68.

Once in this position, fluid flow from within the tool 10 from sub 12 to sub 18 is altered in order to activate the cutting elements 23 supra. Parking tube 42 includes a plurality of equidistant apertures 70 which are in fluid communication with the volume 68. Since sphere 40 blocks fluid flow from within collet sleeve 28, flow is directed via apertures 70 through volume 68 and apertures 64 to contact pistons 24 and thus cutting elements 26.

Once the cutting elements 26 have been deployed and it is desired to reset the cutting elements 26 to a storage position, the same can be reset on—site. This is particularly advantageous from a cost and temporal point of view. Previously with prior art arrangements, the arrangement had to be disassembled and shipped off site in order to retract the reaming or cutting elements. In contrast, the present technology provides a reset member 72, shown in FIG. 3, comprising an elongate member with opposed ends 74 and 76, end 76 having a bushing 78 to abut stop member 44 as shown. In use, the drill bit head, DBH (FIG. 1) may be removed and the reset member 72 inserted through the body of the tool 10. Once the bushing 78 reaching stop member 44, a user continues to advance the member 72 to the position shown in FIG. 4. As illustrated, collet sleeve 28 is returned to the coaxial position within cutter housing 14 and the cutting elements 26 retracted to a storage position. Pistons 24, since they are hydraulically actuated, can simply be pushed back into the storage position. This may also occur as a result of the cutting elements 26 contacting the surface of the borehole during withdrawal. The result is that the cutting elements re retracted into the storage position. With collet sleeve 28 reset, the tool 10 can then be reused.

Referring now to FIGS. 5 through 5C, shown is an alternate embodiment of the present invention. In this embodiment the tool 10, provides an annulus tube 80 with the annulus being in fluid communication with pistons 24. The annulus tube 80 is fixed within cutter housing 14 and in fluid communication with collet sleeve 28, which is truncated in length relative to the previously discussed embodiment. Collet sleeve 28 includes a stop member 82 having a reduced diameter section as shown which services to receive and seat sphere 40, shown in the first position by reference to FIG. 5B. Upon further movement of the sphere 40, the same moves to the position shown in FIG. 5C where the collet sleeve 28 is coaxially received within parking tube 42. As with the previously discussed embodiment, the sphere 40 blocks fluid flow through the tool 10 from sub 12 to sub 18. In this embodiment, the fluid is redirected through apertures 70 of parking tube 42 through to annulus tube 80. Fluid pressure in the annulus builds to actuate pistons 24 and thus cutting elements 26.

FIGS. 6 and 7 illustrate the resetting of the tool 10. Reset member 72 is employed in a similar manner to that discussed for the previous embodiment with the sphere being returned through sub 12 and the retraction of the cutting elements 28. 

We claim:
 1. An expandable reamer apparatus for subterranean drilling, comprising: a tubular body having a longitudinal axis and a trailing end for connecting to a drill string; fluid pressure actuable cutting members movable from a storage position retracted within said tubular body to a use position extending outwardly of said tubular body for reaming and/or expanding the diameter of a borehole; a drilling fluid flow redirection member movably mounted within said tubular body from a first inactive position to a second active position where fluid is redirected adjacent said fluid pressure actuable cutting members to actuate said cutting members to said use position.
 2. The apparatus as set forth in claim 1, wherein said drilling fluid flow direction member is coaxially disposed within said tubular body.
 3. The apparatus as set forth in claim 1, wherein said apparatus includes an annulus tube.
 4. The apparatus as set forth in claim 3, wherein said annulus tube is in fluid communication with said cutting members.
 5. The apparatus as set forth in claim 4, wherein said apparatus includes a coaxially disposed receiving tube for receiving said flow redirection member and redirecting flow to said annulus tube.
 6. The apparatus as set forth in any one of claim 1, wherein said apparatus includes an actuator for actuating said drilling fluid flow redirection member.
 7. The apparatus as set forth in claim 6, wherein said actuator comprises a solid sphere.
 8. The apparatus as set forth in claim 1, wherein said drilling fluid flow redirection member is resettable from said active position to said inactive position.
 9. The apparatus as set forth in claim 8, further including a reset member for effecting movement of said drilling fluid flow redirection member from said active position to said inactive position.
 10. The apparatus a set forth in any one of claim 1, wherein said drilling fluid flow redirection member is disposed coaxially within said body adjacent said fluid pressure actuable cutting members.
 11. The apparatus a set forth in any one of claim 10, wherein said drilling fluid flow redirection member comprises a collet sleeve having a plurality of openings.
 12. The apparatus a set forth in claim 1, wherein said cutting members are manually or self resettable.
 13. A method for reaming a borehole in a subterranean formation, comprising: positioning an expandable reaming apparatus within a subterranean formation, said reaming apparatus having a tubular body, a drilling fluid flow path extending through said tubular body, fluid pressure actuable cutting members movable from a storage position retracted within said body to a use position extending outwardly of said tubular body for reaming and/or expanding the diameter of a borehole; introducing drilling fluid into said reaming apparatus; redirecting said drilling fluid flow in said reaming apparatus with a redirection member movably mounted within said tubular body from a first inactive position to a second active position distal from said cutting members to facilitate drilling fluid flow redirection whereby drilling fluid pressure actuates said cutting members to said use position; and reaming or expanding an expanded borehole in said formation with said apparatus.
 14. The method as set forth in claim 13, wherein said redirection member in said inactive position is adjacent said cutting members.
 15. The method as set forth in claim 13, wherein said redirection member in said inactive position is distal from said cutting members.
 16. The method as set forth in claim 13, further including the step of actuating said redirecting member with an actuating member.
 17. The method as set forth in claim 16, wherein actuating includes positioning a solid sphere at one end of said apparatus.
 18. The method as set forth in claim 13, further including the step of resetting said redirection member.
 19. The method as set forth in claim 18, wherein resetting includes urging said redirection member from said active position to said inactive position with an elongate member.
 20. The method as set forth in claim 16, wherein said cutting members are manually or self resettable. 